1. Field of the Presently Disclosed Inventive Concepts
The inventive concepts disclosed and claimed herein relate to systems and methods for performing surgical procedures and, more particularly, but not by way of limitation, to systems and methods for accessing a surgical target site to perform surgical procedures.
2. Brief Description of Related Art
The present state of the art, when referencing a lateral surgical access approach, typically consists of using the following surgical instruments: neuromonitoring probe, dilators, and a retractor. Once an operative level is identified and an incision is created, dilators are used to create a surgical access site which is often followed by the use of a retractor or other specialized tools to create a surgical access corridor.
During a lateral approach to a patient's spine, a psoas muscle, which is located on either side of the spine, is separated in order to access the spine and, in particular, an intervertebral disc space or one or more vertebral bodies within a patient's spinal column. It is desirable to avoid neural elements or nerves of the lumbar plexus that lie within the psoas muscle during such procedures. The anterior third of the psoas muscle is typically considered a safe zone for muscle separation.
The neural elements or nerves of the psoas muscle may be mapped using a stimulating probe. In this manner, the most posterior neural or nerve-free area of the psoas muscle may be located and identified. The stimulating probe may then be inserted through the psoas muscle via the most posterior neural or nerve-free tissue area or through nearly any other region that is free of neural elements or nerves and toward the spine or into the intervertebral disc space in order to initiate safe tissue separation of the psoas muscle. Dilators are next placed over the probe to create and enlarge a surgical access site. Following the use of dilators, a retractor or other specialized tools are used to further enlarge the surgical access corridor.
Concentric dilators separate the muscle radially, and as such, dilate tissue on all both sides of the stimulating probe in a uniform fashion. This in turn may impinge on neural elements or nerves located outside of the safe zone. Directional dilators have been suggested to overcome the problems associated with concentric dilators. While directional dilation systems are effective for avoiding known neural elements, they are limited in their ability to continuously monitor nerve proximity and to create a surgical access site of a desired shape while at the same time reducing the amount of tissue damage.